nrf52832 bent feed line for wire antenna

Question

Hi, 
 I am designing a custom PCB with the nRF52832, I am going to use wire bent antenna over it. Can I bend feed wire by 45 degree. I have attached image for the part I am talking about. 
 Please have a look and let me know about it 
 .

Andreas · Answer

Hi, 
 
 Yes, that is fine. While you are at it though you should replicate the reference design a little closer, move the inductor down to align with 'ANT_NRF' and grond the parallel capacitor through pin 31 to the center pad, instead of to the ground pour. You should also add a parallel component (not populated yet) right next to the antenna to allow mounting of a tuning capacitor . 
 
 Best regards, 
 Andreas

AmbystomaLabs · Answer

You should model the via and feed. That thru-hole is massive and between that and the uncharacterized bit of trace running to it you could end up with nothing going to your bent wire. If you are planning on producing the product like that you will need to come up with a way to fix the position of the wire, like with a plastic frame. Even small mm changes in its position relative to the board will have huge affects on the RF output. 
 Generally people avoid this type of antenna for the reasons above. You are unlikely to get any consistency in output unless you really nail down the physical characteristics and do a good job matching it. What you are doing really only works well at very low frequencies.

nrf52832 bent feed line for wire antenna

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